Process for utilizing prepared oilbearing material as a filtering agent in solvent extraction by continuous countercurrent flow



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Filed July 2, 1949 ug. 26, 1952 M BONOTTO 2,608,565

PROCESS FOR UTILIZING PREPARED OIL BEARING MATERIAL AS A FILTERING AGENT IN SOLVENT EXTRACTION BY CONTINUOUS COUNTER-CURRENT FLOW 5 Sheets-Sheet 3 Filed July 2, 1949 Mmmm-mn. l-IZOCMOlOEL mmmm tmf-.IIL

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m5 M E R n m H T w H Patented Aug. 26, 1952 vUNITED STATES PATENToF'FlcE PROCESS non UTILIzING PREPARED oIL- BEARING MATERIAL As` A FILTERING AGENT 1N soLvENT ExrRAc'rIoN BY coN- rriNUoUs coUNrEnoURRENT FLOW i Michele Bonotto, Princeton, N. J.

Application July 2, 1949,- SerialNo.-102,7 43

2 Claims. 1

This invention relates to improvementsi in process for utilizing prepared oil bearing material as a iiltering agent in solvent extraction by continuous countercurrent flow.

My present invention is particularly useful in cases where the mechanical characteristics oi the extraction apparatus has a tendency to breal; down the material under process and thus to create nes, and/or when the material has a tendency to disintegrate when it is incontact with the solvent, and/or when it is desired to have the miscella ltered to a higher degree than it is possible to obtain,V through the use of the process disclosed in my said companion application Ser. No. 102,742, :tiled July 2, 1949. I have found that by separating a portion preferably comprising the finer particles of the original material destined for continuous solvent extraction and by processing this portion in a special way so as to give it a diierent physical form and different characteristics than those ofthe original material (via, by pressing or compressing the said nner particles mechanically into cake form and then treating or processing the cake toproduce a coarser product of greater specific gravity than the original material), and thenv by continuously conveying this prepared material as an independent secondary stream into the extractor through a separate inlet and also forcing the outgoing miscella to iiow in countercurrent through a mass orfbody of this prepared material, I am enabled to eiciently lter andentrap the fines in material passing through'a main stream and being extracted.` and find that such lines will be conveyed back toward the outlet for process materialof the extraction and that the carry-over of lines by the miscella through the meeting section is greatly reduced with the result that the discharged miscella is substantially free of suspended solids or fines.

One way or method of preparing thiszphysically different material is to iirst screen orv sieve all the fine particles below a desired size from a given source of oil-bearing material prepared in suitable` form for extraction to provide a main stream of relatively large size that is free'irom lines and a secondary stream containing the said liner solid particles. This may be accomplished by the use of a suitable device such as.

Inisome cases', such as when the original processmaterial is low in oil content, the previously separated iines may,V instead of being passed through a mechanical press for the purpose of extracting.. oil,l be i sent through an i agglomerating machine or device andreduced in agglomerated form of the desired size without attempting to extract part of the oil. In the art, this operation is known as pelltng n In the separate processing hereinabove reierred` to, I` provide insome cases for altering the original soluble content of the screened or separatediines. When processing oil'bearing seeds this is preferably` accomplished, rst. by mechanically pressing such lines to press out oil andlto reduce the screened or separated nes into the form of a cake and. then by granulating it, or reducing them into pellet form,` and preferably by altering the original moisture of the fines to increase their original speciiic weight.' or by a combination of any or all of the above steps.

It will be understood (l)4 that the lines may be separated'` before. the material is passed through` the aking rolls .ifH such material is of a type that does not produce any nes during the iiakine operation, as forexample, oil-bearing seeds or nuts which are plastic and can. be reducedinto flake formwithout producing fines during this operation; (i2)l the fines may be separated after passage of the material through the iiaking rolls; and (3) for materials thatncannot bereduced .i into `iiakeforniv grinders are used to reduce the` uniiakabl`e material into a physical form to suit the solvent extractor. If lines `are produced during this operation, the separation of. the iineswill occur after thelgrinding.`

Ii desired, a iilterf-aidsuch as cellulose` or iibrous material insuch formas to ass-istinthe action of my prepared material as a filteringmaterial may be added to the separated fines or to the processed nes. i

In accordancefwith my present invention, the inlet sectionror zone of the extractor is divided into two sections, viz., amain entering or feeding section for process-material through whichthe mainstream of materialminus the iine particles that have been screenedcutlas described above and through` which `inlet-section` the. miscella is not, on its Way out of thelextractor, `allowed to pass, and an independent or separate inlet (which shall designatelas ajsecondary inlet)f for the specially-processed ori prepared fine particles which willbe soarranged as to provide the-meeting section ofthe extractor, by which I mean the section of the extractor which is adjacent to the outlet for the outgoing stream of liquid miscella and through which said miscella moves in its passage from the extractor and within which section there is a normal tendency to carry with the miscella a certain amount of minute solid particles or iines, which in the usual process in an extractor, being buoyant in the miscella, are picked up by such miscella and separated from the solid process material containing them which is moving or passing in countercurrent with such miscella through the extractor.

In accordance with my instant invention, the miscella is allowed to percolate through the prepared material in this secondary inlet portion on its Way out of the extractor with -a resulting improved filtering action. The clarity of the discharged miscella will also be improved by the fact that the percentage of the fine particles originally contained in the main stream is no longer present in said main stream while the iltering action will be improved because the main stream does not cross the filtering section and because the ne particles originally present have been changed into a new physical form or agglomerated into particles of larger size by the processing or preparation hereinabove mentioned.

' In accordance with my present invention the two streams of solids are joined together within the extractor below said meeting section and then travel together through said extractor.

My lpresent invention is particularly useful in the continuous'countercurrent solvent extraction of cottonseed, peanuts, axseed and other similar oil-bearing seeds and of packing-house by-products that have a tendency to partially disintegrate under the action of solvent in the extraction apparatus and that also have a tendency to produce a considerable amount of ne particles during their preparation to ready them for solvent extraction.

With these and other objects in view, the inventioncomprises the combination of members and arrangement of parts so combined as to coact and cooperate with each other in the performance of the functions and the accomplishment of the results herein contemplated, and comprises in one of its adaptations the species or preferred form illustrated in the accompanyingdrawings, in which: y Y

Fig. 1 is a diagrammatic View illustrating the steps used in my process and the apparatus including an extraction column in section that is employed in carrying out a preferred form of my invention;

Fig. 2 is a View in section of a modied form of extraction apparatus that may be employed in carrying out my invention; y

Fig. 3 is a view in section of another modified form of extraction apparatus that may be employed by me; and Y Fig. 4 is a sectional view of still another form of apparatus that may be employed by me in carrying out my invention.

The main difference between my present invention and the prior art in filtering the outgoing miscella by the material going to the extractor is that in prior art apparatus and processes, the miscella percolates through a chargel of material originally prepared for extraction and having the original physical characteristics that it had when leaving the preparation machinery, while in my present invention the miscella is caused to percolate through part of the original material which has been previously and separately processed in a special way and which enters the extractor through a special or independent inlet.

I shall describe my new process in detail, using as an example its utility in extracting cottonseed. A l The cottonseed is first delinted and hulled in the conventional Way, and in Fig. 1 I have shown a storage receptacle I of the hulled cottonseed meats. After conveyance by conveyor 2 and conventional conditioning in a conditioner 3, the meats are conveyed by conveyor 4 to and reduced into flake form by passage through conventional fiaking rolls 5. The stream 6 of flakes from the iiaking rolls 5 is then passed through a conventional reel or screen 1, and thus divided into two streams 8 and 9. The material remaining on top of the screen constitutes and is designated as the main stream 8 and is continuously and uninterruptedly conveyed to the extraction system or Acolumn I9 and, as shown, is introduced into said column III through the inlet II, while the matef rial that has passed through the screen constitutes and is designated as the secondary stream 9. v

In the case of cottonseed, the secondary stream 9 isconveyed by conveyor 9a to and is passed through a continuous mechanical press I2 where a substantial part of the oil is mechanically removed and passed through pipe I3 to a suitable receptacle not shown and this oil, if desired, may be mixed withsolvent extracted oil.

The cake from the press I2 is continuously conveyed by conveyor 9b and passed through a conditioner I5 where moisture is added and the temperature is raised for the purpose of prevent# ing the creation of nes during a subsequent granulation or grinding operation in a granulator I6 to which the cake is passed by conveyor SC. The granulated fines coming from the granulator and, as hereinbefore stated, constituting the secondary stream 9 are conveyed by conventional` means such as the conveyor 9d to the extractor IB through inlet I'i.

The miscella outlet. I8 is located in a suitableplace or point in the secondary inlet I1 so that miscella being discharged from the column itl must percolate through a bed of material in said secondary inlet ilbefore reaching the outlet. rIhe miscella is forced to flow through the outlet I3 because the column of material Il leading to the inlet vI I, including the feed-hopper llc extends to a higher level than does the column of material I'Ib and feed-hopper Ilc connected with the inlet Il and has no outlet for the miscella. The meeting section, consequently, is located at the zone indicated and this section or zone contains only prepared material from the secondary-stream 9 and the size of this conglomerated'or. granulated material is such that it cannot be carried out with the outgoing miscella owing'through said meeting section. The 'area ofv the 'meeting section will be calculated so as to control the velocity of the liquid miscella'and to keep carryingpower thereof below and in proper relationship with the size and specific gravity of the particles of material constituting the secondary stream.

T he main stream 8 entering through the inlet II and the material constituting the secondary stream 9 entering through the inlet Il will mix together in the zone [9 and then proceed through the extractor towards the exit, together with 5 Whatever fines were entrapped 1n the filtering bed.

It will be understood that the fine-separation which causes the creation of the main and the secondary streams may be accomplished at any point during the preparation of the material for solvent extraction. For instance, this separation may take place before the material to be extracted enters the i'iaking rolls, as described in companion application Ser. No. 102,742, iiled July 2, 1949.

Fig. 2 shows another modified form of extraction apparatus for processing or extracting material from the main and secondary streams such as hereinabove described. In Fig. 2 two percolating zones are provided and the secondary stream enters laterally into the extraction column and is provided with a laterally-disposed intermediate feed-conduit 2l). In other respects, it is substantially similar to the construction shown in Fig. 1, the higher column 2l being fed by the main stream 8 and the relatively-low column 22 being fed by the secondary stream 9.

Fig. 3 shows fragmentarily a modified `form of an extraction column which contains annular screen 23 through which the miscella passes on its way out of the column, and an outer annular relatively-low column 24 of material fedfrom the secondary stream 9 while a centrally-disposed column 25 reaching to a higher level is suitably mounted Within said outer column 24 H and is fed from a main stream 8.

Fig. 4 illustrates another modied form shown in connection with a lter feeder. In this arrangement, at the bottom of the percolating bed inthe column 26 I provide a proportion feeder 2l located so as to allow only a part of the processed granulated `fines to be fed into the Redler conveyor 28. Without this proportion feeder, due to the characteristics of the Redler conveyor 2B the casing would be full of material coming from the hopper 2Sa and no room would be left for material unloaded from the hopper 29a. of the column 29. The high column 29 is similarly fed by the main stream 8 and the relatively low column 26 is fed by the secondary stream 9.

Having described my invention, I claim:

l. A process for the solvent extraction of oilbearing materials consisting in screening of a naked solvent-extractable oil-bearing material to separate as screenings therefrom a quantity of minute particles comprising nes, mechanically pressing such minute particles derived from such screening to produce a product having granular pieces each composed of a compressed and granu-v lated mass of coarser and increased size than said screening and of greater density than the material from which the granulated pieces were derived, and utilizing such compressed and granulated pieces as a ltering material in the extraction of the solvent-extractable oil-bearing material from which such compressed and granulated pieces have been derived.

2. A process for the solvent extraction of oilbearing materials as claimed in claim 1 in which the compressed material is fed as a separate and independent miscella-filtering product into the meeting section of an extractor in a, counter- .current extraction operation.

MICHELE BONOTTO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,694,361 Sterling Dec. 4, 1928 2,264,390 Levine et al Dec. 2, 1941 2 430,535 Schmidt et al Nov. 11, 1947 2,445,931 Beckel July 27, 1948 

1. A PROCESS FOR THE SOLVENT EXTRACTION OF OILBEARING MATERIALS CONSISTING IN SCREENING OF A FLAKED SOLVENT-EXTRACTABLE OIL-BEARING MATERIAL TO SEPARATE AS SCREENING THEREFROM A QUANTITY OF MINUTE PARTICLES COMPRISING FINES, MECHANICALLY PRESSING SUCH MINUTE PARTICLES DERIVED FROM SUCH SCREENING TO PRODUCE A PRODUCT HAVING GRANULAR PIECES EACH COMPOSED OF A COMPRESSED AND GRANULATED MASS OF COARSER AND INCREASED SIZE THAN SAID SCREENING AND OF GREATER DENSITY THAN THE MATERIAL FROM WHICH THE GRANULATED PIECES WERE DERIVED, AND UTILIZING SUCH COMPRESSED AND GRANULATED PIECES AS A FILTERING MATERIAL IN THE EXTRACTION OF THE SOLVENT-EXTRACTABLE OIL-BEARING MATERIAL FROM WHICH SUCH COMPRESSED AND GRANULATED PIECES HAVE BEEN DERIVED. 